"Sat, 17 Jan 1970 18:14:15"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700117
Only TIME
18:14:15
General datetime
1970-01-17 18:14:15Z
For Database
1970-01-17 18:14:15
For HTTP1.1
Sat, 17 Jan 1970 18:14:15 GMT